Rubber mill



Dec. 2, 1969*? J. T. MATSUOKA 3,

RUBBER MILL Filed June 19. 1967 INVENTOR JAMES T MATSUOKA ATTORNEYS United States Patent 3,480,992 RUBBER MILL James T. Matsuoka, Brecksville, Ohio, assignor, by mesne assignments, to Intercole Automation, Inc., a corporation of Ohio Filed June 19, 1967, Ser. No. 647,168 Int. Cl. B29h 1/00 US. Cl. 18-2 3 Claims ABSTRACT OF THE DISCLOSURE A rubber mill having horizontal driven rolls supported between end housings, with a base structure recessed on each side of the mill between the end housings to permit an operator to stand close to the rolls.

BACKGROUND The present invention relates to mills for processing plastic material and commonly referred to as rubber mills.

Plastic processing mills of the character here involved comprise two heavy rolls driven by suitable means, usually an electric motor. The rolls are arranged horizontally with respect to one another with a slight space therebetween. The material to be processed is placed on top of the rolls and is worked or processed by the action of the rolls which are rotated in appropriate directions and at appropriate speeds as is well understood in the art. The material being processed periodically requires some manipulation or handling by an operator. For example, the material being worked often becomes stuck on the rolls, requiring the operator to reach over the top of the rolls to pull the stuck material away. In the case of large mills, for example, mills with rolls eighteen inches or more in diameter, it is difiicult for the operator to reach over the rolls. Part of this difficulty is caused by the fact that the base structure of the mills has extended outwardly of the rolls at one or both sides of the mill to an extent that makes it difficult for the operator to stand close to the rolls.

SUMMARY The rubber mill of the present invention utilizes a frame comprised of two spaced end housings that support the rolls and a base that is recessed or inset relative to the end housings along both the front and rear sides of the mill between the end housing.

The principal object of the present invention is the provision of a novel and improved mill of the type referred to having a base structure such that the part thereof between the end housings that support the rolls is recessed or inset on each side of the mill with respect to front and rear sides of the end housings so that the operator can comfortably stand on either side of the mill close to the rolls and effectively reach over the rolls to pull away material stuck to the rolls and otherwise manipulate or handle the work.

A further object of the present invention is the provision of a novel and improved plastic mill of the type referred to having a base structure that is recessed on each side of the mill with respect to the front and rear side of the end housings and extends laterally of the mill beyond the rolls a distance no greater than 50 percent of the roll diameter.

These and further objects and advantages of the invention will be apparent from the following description of a preferred embodiment described with reference to the ac- 3,480,992 Patented Dec. 2, 1969 "ice companying drawing forming a part of this specification in which like reference characters designate corresponding parts and in which:

FIGURE 1 is a perspective view of a mill for processing plastic material embodying the present invention; and

FIGURE 2 is a transverse sectional view taken in a transverse plane approximately at the line 22 of FIG- URE 1; and

FIGURE 3 is a fragmentary view on an enlarged scale of the base portion of the mill as shown in FIGURE 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGURE 1, a plastic processing mill shown therein and indicated generally by reference numeral 10 is comprised basically of two horizontal processing rolls 12, 14 in side-by-side relationship, and a sup-porting frame that includes two spaced end housings 16, 18 and a narrow base structure indicated generally at 20. Opposite ends of the rolls 12, 14 are journalled in journal boxes 21 supported in the end housings 16, 18. The journal boxes which carry the roll 12 are fixed in the end frames and the roll is driven by an electric motor, not shown. The journal boxes which carry the roll 14 are movable toward and away from the fixed journal boxes which carry the roll 12 and the roll 14 is driven by the roll 12 through gears connected to adjacent ends of the rolls and covered by a gear guard 22. Typical production mills use rolls that are 14 to 28 inches in diameter.

The end housings, 16, 18 are identical, and only the end housing 16 will be described in detail. The end housing 16 includes a U-shaped mill frame 26 that receives and supports the journal boxes 21 at the near end of the rolls 12, 14, as viewed in FIG. 1. The mill frame 26 includes a generally horizontal base portion 27 and spaced upright side portions 28, 29, the front and rear sides of which initially curve outwardly and upwardly from the base portion 27 and then extend essentially vertically. A top cap 32 fits across the upper ends of the upright side portions 28, 29 and is secured in place by suitable fasteners 34, 35. The mill frame 26 and top cap 32 define an open central area 37. The journal boxes 21 are received in the central area 37 and are supported on the base portion 27 of the mill frame. The journal box for roll 14 is slidable along the base portion 27 to change the distance between the rolls 12, 14. To facilitate this, an adjusting screw 36 is provided in the upright side portion 28 for moving the journal box. Typically, an end housing that accommodates relatively large rolls of 22 to 26 inches in diameter may be about 84 inches wide and 45 inches high, with a central opening 60 inches wide and 23 inches high.

Integral pedestal brackets or feet 38 which, as. shown, extend from opposite sides of the base portion 27 of the mill frame 26 near opposite ends thereof, adjacent the upright side portions 28, 29. As best shown in FIGURE 2, the pedestal brackets 38, 39 are located inwardly of outside surfaces 28a, 29a of upright side portions 28, 29, respectively. The inset location of the pedestal brackets 38, 39 facilitate the use of a narrow base structure 20 which does not extend outwardly of the pedestal brackets, thereby permitting an operator to stand much closer to the rolls 12, 14 on both sides of the mill, than heretofore possible. The brackets 38, 39 are set back or inset at least 6 inches behind the respective outside surfaces 28a, 29a of the mill frame 26, and preferably a distance of about one foot. In the preferred embodiment, as shown in FIG- URE 2, the pedestal brackets 38, 39 are located inwardly of the central opening 37 of the end housing 16, placing them in lateral proximity to the rolls 12, 14.

The base structure 20, as shown, is formed of longitudinal H-beams or wide flanged I-beams 42, 43 and connecting cross beams 44, 45. The longitudinal beams 42, 43 extend between the end housings 16, 18 and are laterally spaced so that the longitudinal beam 42 underlies the pedestal brackets 39 of each end housing, and the longitudinal beam 43 underlies the pedestal brackets 38 of each end housing. The connecting cross beam 44 is located directly beneath the base portion 27 of the end housing 16, and the connecting beam 45 is directly beneath the base portion of the end housing 18. Pedestal blocks or mounting pads 48, 49 underlie each pedestal bracket 38, 39 of the end housing 16, 18 and are secured to the beams. The pedestal brackets 38, 39 are secured to the pedestal blocks 48, 49.

The longitudinal beams 42, 43 limit how close an operator can approach the rolls 12, 14 without climbing upon the base structure. Because it is often necessary for the operator to manipulate the work during operation, it is desirable that the mill be constructed to allow the operator to comfortably stand as close to the rolls as safety permits. In particular, it is difficult for the operator to pull away material which may be stuck on the rolls if he must lean forward an appreciable amount to reach the material. The location of the pedestal brackets 38, 39 and the construction and location of the beams 42, 43 allow the operator to stand close to the rolls, preferably close enough so that he can lean away from the rolls while working with the material, thus giving him good pulling leverage. Because the material often sticks in a manner that requires the operator to get to the back roll to pull the material free, it is essential that the base structure permit the operator to stand close to the rolls on both sides of the frame.

As best shown in FIGURE 2, the pedestal brackets 38, 39 are located inwardly with respect to the outer surfaces 28a, 29a of the upright side portions 28, 29 of the end housings 16, 1-8. Other limits of the beams 42, 43, defined by upper and lower outer flange edges 50, 51 and 52, 53, respectively, are essentially laterally coextensive with the pedestal brackets and define outer limits of the base 20 between the end housings 16, 18, Not only are these outer limits of the beams located laterally inward with respect to the outer surfaces 28a, 29a of the end housing, but also the use of H-beams provides substantial additional space for the front portions of the feet of operator, which may extend inwardly of the lower beam edges 51, 52 to the inset vertical webs 54, 55.

The longitudinal beams 42, 43 themselves at least partially underlie the rolls 12, 14. As shown in FIGURE 2, the longitudinal beams are preferably located to entirely underlie the central area 37 of each end housing 16, 18 in which the rolls are supported, thus locating the base support beneath the weight of the rolls and out of the way of the operator.

To provide access to the rolls such that the operator can readily reach across a roll to the work, the outer limits of the base structure should not extend laterally beyond the periphery of the roll on either side of the mill more than a distance equivalent to 50 percent of the roll diameter and typically it will extend no more than a distance equivalent to between 25 and 45 percent of the roll diameter. While the actual distance an operator will have to reach will of course vary with mills of different sizes, the above relationship will allow the operator to adequate ly approach the roll on the largest mills and will assure even greater convenience with smaller mills.

To recess the base and provide desirable clearance for the operator while yet providing a stable support, the outside longitudinal edges 51, 52 of the base should be spaced apart between 70 and 85 percent of the width of the end housings 16, 18. In addition, as a minimum and consistent with the above relationships, the pedestal brackets should be inset and the outer edge of the base structure should be located inwardly on each side of the mill a distance of at least 6 inches from the outside surfaces 28a, 29a of the upright portions 28, 29 of the end housings, to provide room for the front part of the operators feet as he stands at either side of the mill, aligned with the upright side surface portions 28a, 29a. In the case of a base formed of H-beams, additional space will be provided since the operator can stand with the front part of his feet on the lower flange of the beam.

In some mills, a safety bar extends between the end housings so that the operator cannot approach the rolls beyond a predetermined point without automatically stopping the mill. Safety bars 56, 57 of this type are shown on each side of the rolls 12, 14 in FIGURES 1 and 2 of the drawings. The safety bars 56, 57 are each supported by a bell crank lever 59 at each end, pivotally connected to the associated end housings 16, 18. Movement of the safety bar causes the bell crank levers to rotate and actuate safety switches that stop the rotation of the rolls. As best illustrated in FIGURE 2, the underslung end housings and narrow base structure 20* locates the outer longitudinal edges 51, 52 of the base structure inwardly of the safety bars 56, 57. As a result, the operator can stand as close to the rolls as the safety bars will permit, without interference from the base structure 20 with his feet.

From the above disclosure, it will be evident that a mill for processing plastic material has been provided with end housings and base structure that permits an operator to comfortably and conveniently approach the rolls and which yet supports the mill with adequate stability.

While in the foregoing disclosure a preferred embodiment of this invention has been disclosed, it will be understood that numerous modifications or alterations may be made therein without departing from the spirit and scope of the invention, as set forth in the appended claims.

What is claimed is:

1. In a mill for processing plastic material: a frame comprising spaced end housings and supporting base structure; a pair of side-by-side processing rolls extending longitudinally between said spaced end housings, supported for rotation about generally horizontal axes; said end housings each having front and rear sides projecting forwardly and rearwardly in a lateral direction beyond said rolls; and said base structure, forming a part of said frame, connecting said end housings together and having the portion thereof between said end housings located laterally inward of the front and rear sides of the end housings and laterally outward from the periphery of the adjacent processing roll on each side of the frame a distance no greater than about fifty percent (50%) of the diameter of the adjacent processing roll.

2. In a mill for processing plastic material: a frame comprising spaced end housings and supporting base structure adapted to rest on a floor; a pair of side-by-side processing rolls extending longitudinally between said spaced end housings, supported for rotation about generally horizontal axes; said end housings each having front and rear side portions spaced apart laterally beyond the rolls; and said base structure, forming a part of said frame, having a portion underlying and connecting said end housings together, which portion has outer longitudinally extending sides between the end housings that are located at least 6 inches laterally inward on each side of the mill from the outer surfaces of the front and rear side portions of the end housings.

3. In a mill for processing plastic material, a frame comprising: longitudinally spaced transverse end housings for supporting a pair of longitudinally extending side-byside rolls, each end housing being generally U-shaped, and having a horizontal lower portion, laterally spaced upright side portions extending from said horizontal lower portion with outwardly facing lateral surfaces that curve initially outward and upward from the lower portion, a

5 top cap extending above the lower portion across and secured to the said upright side portions, and integral pedestal brackets on the horizontal lower portion of each end housing located laterally inward of said outwardly facing lateral surfaces and extending longitudinally from the lower portion; a base extending between and beneath said end housing, no greater in width than the distance between outer lateral edges of the integral pedestal brackets on each end housing; and means connecting said pedestal brackets to said base.

6 References Cited UNITED STATES PATENTS 357,700 2/1887 Cowen. r) 544,294 8/ 1895 Evans. 1,405,383 2/ 1922 Abbott. 1,535,392 4/1925 Ashton. 1,780,112 10/1930 Bowman.

J0 WILLIAM J. STEPHENSON, Primary Examiner 

